1. Field of the Invention
This invention generally relates to disc brakes for stopping rotation of a wheel of a bicycle. More specifically, the present invention relates to a fluid cooling system for cooling a bicycle disc brake.
2. Background Information
Bicycling is becoming an increasingly popular form of recreation as well as a means of transportation. Moreover, bicycling has become a very popular competitive sport. Whether the bicycle is used for recreation, transportation or competition, the bicycle industry is constantly improving their components. One particular component of the bicycle which has been extensively redesigned over the past years is the braking systems of bicycles.
There are several types of bicycle brake devices, which are currently available on the market. Examples of some types of common bicycle brake devices include rim brakes, caliper brakes and disc brakes. If a rider wants a very high performance brake system, then the rider typically wants a disc brake system. Disc brake systems provide a substantial braking power in relationship to the amount of braking force applied to the brake lever. Moreover, disc brake systems typically provide a high level of consistency in all types of weather and riding conditions. However, one problem with disc brakes is that the hydraulic or actuating fluid can become overheated such that vapor-lock occurs. In other words, the heat generated by braking results in the hydraulic fluid increasing in volume so as to cause the brake pads to engage the brake disc even when the brake lever is in the release position. When vapor-lock occurs, the bicycle wheels can lock up and throw the rider off of the bicycle.
In the prior art disc brake systems, several methods have been utilized to avoid vapor-lock. For example, the caliper housing can be made larger to absorb more heat. Another method has been to make a larger brake disc with a wider surface area. Also, vapor-lock can be suppressed by utilizing high quality hydraulic fluid. Yet another method to avoid vapor-lock has been to use brake or friction pads which do not transfer the heat to the brake housing as readily as conventional friction pads. These prior art methods of avoiding vapor-lock have many problems. One particular problem, is that these solutions often are expensive to manufacture. Also, some of these prior art solutions are not completely effective.
In view of the above, there exists a need for a fluid cooled disc brake for a bicycle which overcomes the above-mentioned problems in the prior art. This invention addresses these needs in the prior art as well as other needs, which will become apparent to those skilled in the art from this disclosure.